Subversion Repositories HelenOS-historic

Rev

Rev 477 | Rev 501 | Go to most recent revision | Only display areas with differences | Ignore whitespace | Details | Blame | Last modification | View Log | RSS feed

Rev 477 Rev 483
1
/*
1
/*
2
 * Copyright (C) 2005 Ondrej Palkovsky
2
 * Copyright (C) 2005 Ondrej Palkovsky
3
 * All rights reserved.
3
 * All rights reserved.
4
 *
4
 *
5
 * Redistribution and use in source and binary forms, with or without
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
6
 * modification, are permitted provided that the following conditions
7
 * are met:
7
 * are met:
8
 *
8
 *
9
 * - Redistributions of source code must retain the above copyright
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
15
 *   derived from this software without specific prior written permission.
16
 *
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
27
 */
28
 
28
 
29
#ifndef __mips32_ATOMIC_H__
29
#ifndef __mips32_ATOMIC_H__
30
#define __mips32_ATOMIC_H__
30
#define __mips32_ATOMIC_H__
31
 
31
 
32
#include <arch/types.h>
32
#include <arch/types.h>
33
 
33
 
34
#define atomic_inc(x)   (a_add(x,1))
34
#define atomic_inc(x)   ((void) atomic_add(x, 1))
35
#define atomic_dec(x)   (a_sub(x,1))
35
#define atomic_dec(x)   ((void) atomic_add(x, -1))
36
 
36
 
37
#define atomic_inc_pre(x) (a_add(x,1)-1)
37
#define atomic_inc_pre(x) (atomic_add(x, 1) - 1)
38
#define atomic_dec_pre(x) (a_sub(x,1)+1)
38
#define atomic_dec_pre(x) (atomic_add(x, -1) + 1)
39
 
39
 
40
#define atomic_inc_post(x) (a_add(x,1))
40
#define atomic_inc_post(x) atomic_add(x, 1)
41
#define atomic_dec_post(x) (a_sub(x,1))
41
#define atomic_dec_post(x) atomic_add(x, -1)
42
 
42
 
43
 
43
 
44
typedef volatile __u32 atomic_t;
44
typedef volatile __u32 atomic_t;
45
 
45
 
46
/*
-
 
47
 * Atomic addition
46
/* Atomic addition of immediate value.
48
 *
47
 *
49
 * This case is harder, and we have to use the special LL and SC operations
-
 
50
 * to achieve atomicity. The instructions are similar to LW (load) and SW
-
 
51
 * (store), except that the LL (load-linked) instruction loads the address
-
 
52
 * of the variable to a special register and if another process writes to
-
 
53
 * the same location, the SC (store-conditional) instruction fails.
48
 * @param val Memory location to which will be the immediate value added.
54
 
-
 
55
 Returns (*val)+i
-
 
56
 
-
 
57
 */
-
 
58
static inline atomic_t a_add(atomic_t *val, int i)
49
 * @param i Signed immediate that will be added to *val.
59
{
-
 
60
    atomic_t tmp, tmp2;
-
 
61
 
-
 
62
    asm volatile (
-
 
63
        "   .set    push\n"
-
 
64
        "   .set    noreorder\n"
-
 
65
        "   nop\n"
-
 
66
        "1:\n"
-
 
67
        "   ll  %0, %1\n"
-
 
68
        "   addu    %0, %0, %3\n"
-
 
69
        "       move    %2, %0\n"
-
 
70
        "   sc  %0, %1\n"
-
 
71
        "   beq %0, 0x0, 1b\n"
-
 
72
        "   move    %0, %2\n"
-
 
73
        "   .set    pop\n"
-
 
74
        : "=&r" (tmp), "=o" (*val), "=r" (tmp2)
-
 
75
        : "r" (i)
-
 
76
        );
-
 
77
    return tmp;
-
 
78
}
-
 
79
 
-
 
80
 
-
 
81
/*
-
 
82
 * Atomic subtraction
-
 
83
 *
50
 *
84
 * Implemented in the same manner as a_add, except we substract the value.
-
 
85
 
-
 
86
 Returns (*val)-i
51
 * @return Value after addition.
87
 
-
 
88
 */
52
 */
89
static inline atomic_t a_sub(atomic_t *val, int i)
53
static inline atomic_t atomic_add(atomic_t *val, int i)
90
 
-
 
91
{
54
{
92
    atomic_t tmp, tmp2;
55
    atomic_t tmp, v;
93
 
56
 
94
    asm volatile (
57
    __asm__ volatile (
95
        "   .set    push\n"
-
 
96
        "   .set    noreorder\n"
-
 
97
        "   nop\n"
-
 
98
        "1:\n"
58
        "1:\n"
99
        "   ll  %0, %1\n"
59
        "   ll %0, %1\n"
100
        "   subu    %0, %0, %3\n"
60
        "   addiu %0, %0, %3\n" /* same as addi, but never traps on overflow */
101
        "       move    %2, %0\n"
61
        "       move %2, %0\n"
102
        "   sc  %0, %1\n"
62
        "   sc %0, %1\n"
103
        "   beq %0, 0x0, 1b\n"
63
        "   beq %0, %4, 1b\n"   /* if the atomic operation failed, try again */
104
        "       move    %0, %2\n"
64
        /*  nop */      /* nop is inserted automatically by compiler */
105
        "   .set    pop\n"
-
 
106
        : "=&r" (tmp), "=o" (*val), "=r" (tmp2)
65
        : "=r" (tmp), "=m" (*val), "=r" (v)
107
        : "r" (i)
66
        : "i" (i), "i" (0)
108
        );
67
        );
-
 
68
 
109
    return tmp;
69
    return v;
110
}
70
}
111
 
71
 
112
 
72
 
113
#endif
73
#endif
114
 
74